Learning curves for pediatric laparoscopy: how many operations are enough? The Amsterdam experience with laparoscopic pyloromyotomy

Few studies on the surgical outcomes of open (OP) versus laparoscopic pyloromyotomy (LP) in the treatment of hypertrophic pyloric stenosis have been published. The question arises as to how many laparoscopic procedures are required for a surgeon to pass the learning curve and which technique is best in terms of postoperative complications. This study aimed to evaluate and quantify the learning curve for the laparoscopic technique at the authors' center. A second goal of this study was to evaluate the pre- and postoperative data of OP versus LP for infantile hypertrophic pyloric stenosis. A retrospective analysis was performed for 229 patients with infantile hypertrophic pyloric stenosis. Between January 2002 and September 2008, 158 infants underwent OP and 71 infants had LP. The median operating time between the OP (33 min) and LP (40 min) groups was significantly different. The median hospital stay after surgery was 3 days for the OP patients and 2 days for the LP patients (p = 0.002). The postoperative complication rates were not significantly different between the OP (21.5%) and LP (21.1%) groups (p = 0.947). Complications were experienced by 31.5% of the first 35 LP patients. This rate decreased to 11.4% during the next 35 LP procedures (p = 0.041). Two perforations and three conversions occurred in the first LP group, compared with one perforation in the second LP group. The number of complications decreased significantly between the first and second groups of the LP patients, with the second group of LP patients quantifying the learning curve. Not only was the complication rate lower in the second LP group, but severe complications also were decreased. This indicates that the learning curve for LP in the current series involved 35 procedure

A FRET-Based High Throughput Screening Assay to Identify Inhibitors of Anthrax Protective Antigen Binding to Capillary Morphogenesis Gene 2 Protein

Anti-angiogenic therapies are effective for the treatment of cancer, a variety of ocular diseases, and have potential benefits in cardiovascular disease, arthritis, and psoriasis. We have previously shown that anthrax protective antigen (PA), a non-pathogenic component of anthrax toxin, is an inhibitor of angiogenesis, apparently as a result of interaction with the cell surface receptors capillary morphogenesis gene 2 (CMG2) protein and tumor endothelial marker 8 (TEM8). Hence, molecules that bind the anthrax toxin receptors may be effective to slow or halt pathological vascular growth. Here we describe development and testing of an effective homogeneous steady-state fluorescence resonance energy transfer (FRET) high throughput screening assay designed to identify molecules that inhibit binding of PA to CMG2. Molecules identified in the screen can serve as potential lead compounds for the development of anti-angiogenic and anti-anthrax therapies. The assay to screen for inhibitors of this protein–protein interaction is sensitive and robust, with observed Z' values as high as 0.92. Preliminary screens conducted with a library of known bioactive compounds identified tannic acid and cisplatin as inhibitors of the PA-CMG2 interaction. We have confirmed that tannic acid both binds CMG2 and has anti-endothelial properties. In contrast, cisplatin appears to inhibit PA-CMG2 interaction by binding both PA and CMG2, and observed cisplatin anti-angiogenic effects are not mediated by interaction with CMG2. This work represents the first reported high throughput screening assay targeting CMG2 to identify possible inhibitors of both angiogenesis and anthrax intoxication

Open Versus Laparoscopic Pyloromyotomy for Hypertrophic Pyloric Stenosis: A Systematic Review and Meta-Analysis Focusing on Major Complications

BACKGROUND: There is an ongoing debate about whether laparoscopic pyloromyotomy (LP) or open pyloromyotomy (OP) is the best option for treating hypertrophic pyloric stenosis (HPS). The aim of this study was to compare the results of both surgical strategies by means of a systematic review and meta-analysis of the available literature. METHODS: A systematic search for randomized clinical trials (RCTs) comparing OP and LP was conducted. Studies were reviewed independently for quality, inclusion and exclusion criteria, and outcomes. Primary outcome was major postoperative complications (i.e., incomplete pyloromyotomy, perforation, and need for reoperation). Secondary outcomes were time to full feed, postoperative hospital stay, and any other postoperative complications. RESULTS: Four RCTs with a total of 502 patients (OP 255, LP 247) fulfilled the inclusion criteria and were analyzed in this review. These trials showed an absolute incidence of major postoperative complications of 4.9% in the LP group. Meta-analysis showed that LP did not lead to significantly more major postoperative complications (ARR 3%, 95% CI −3 to 8%) than OP. The mean difference in time to full feed was significant (2.27 h, 95% CI −4.26 to −0.29 h) and the mean difference in postoperative hospital stay tended to be shorter (2.41 h, 95% CI −6.10 to 1.28 h), both in favor of LP. CONCLUSION: So far, the major postoperative complication rate after LP for HPS is not substantially higher than after OP. Because time to full feed and postoperative hospital stay are at best a few hours shorter after LP than after OP, the laparoscopic technique might be acknowledged as the standard of care if the major postoperative complication rate is low. Hence, this laparoscopic procedure should preferably be performed in centers with pediatric surgeons with expertise in this procedure